A hitch assembly connects a towing vehicle with a towed vehicle, such as a trailer. One common type of hitch assembly includes a hitch ball on the towing vehicle. The hitch ball is often removably mounted on a ball mount secured to the frame of the towing vehicle. The ball mount includes a through hole for receiving a shank portion of the hitch ball. The hitch ball is secured to the ball mount with a fastener that is threaded on the shank portion and tightened down against the ball mount.
During assembly, if the hitch ball is rotated by a wrench, socket driver, or other tool, the fastener tends to rotate along with it. Similarly, if the fastener is rotated by a tool, the hitch ball has a tendency to rotate also. Therefore, to tighten the hitch ball and fastener onto the ball mount, one of the hitch ball or fastener must be blocked from rotating relative to the ball mount while the other is rotated. Typically, this is accomplished by using two wrenches to grasp both the hitch ball and fastener. One wrench is used to hold either the hitch ball or the fastener stationary, while the other wrench is used to tighten down the other.